Patent GB-1435986-A (GB)
Title: Parts supply apparatus
IPC: B65G43/08
Filed: 1973-11-23
Abstract: 1435986 Discharging from shoots and hoppers MATSUSHITA ELECTRIC INDUSTRIAL CO Ltd 23 Nov 1973 [25 Nov 1972 (2)] 54569/73 Heading B8S [Also in Division F1] Fasteners, e.g. screws or rivets, are stored in a hopper 2 from which they are discharged on to a guide tray 17 by means of scoops 4 disposed on the inner side of a rotary drum 3, the fasteners passing from the tray 17 down a shoot 16a, 16b to a distributer 18 which feeds them one at a time along a pipe 50 to a fastening device 51, Fig. 11. The drum 3 is rotated by means of an air ram 6, actuation of which is controlled by sensing means which detects the state of supply of fasteners in the shoot, and there is a first pneumatic control circuit which effects drive control over the ram 6 and a second pneumatic control circuit associated with the distributer 18 and fastening device (51) for activating the distributer to supply fasteners to the device (51), both control circuits being shown in Fig. 11. The sensing means is shown in Fig. 4 and comprises two yoke-shaped signal emitters 28, 29 located below the shoot 16a, 16b, each having a gap across which air is blown from an opening 34a to an opening 35a, and from an opening 34b to an opening 35b respectively. Located above the shoot 16a, 16b is a board 20a having an air channel 30 formed therein supplying air to nozzles 32a, 32b, located above the signal emitters 28, 29 respectively. If there are no fasteners in the shoot the jets of air emitted from the nozzles 32a, 32b interrupt the air jets passing across the gaps in the members 28, 29 which thus provide no signal from their respective outputs, the latter being connected respectively to the inputs 78A, 78B of a NOR monostable element 78, Fig. 11, the absence of signals producing an output from the element 78 which is fed to the input 80A of a bi-stable element 80 which produces an output signal at 80 F2 which is fed along a line P8 to open a switch valve B1 whereby air coming from an air compressor AC along a line P6 is passed through the valve B1 to an oscillator 82 which actuates the ram 6 and thus the drum which feeds fasteners into the shoot 16a, 16b. When the fasteners in the shoot reach the level of the upper signal emitter 28 each of the signal emitters 28, 29 emits an output pulse to the monostable element 78, that signal from the emitter 28 passing along a line P102 to a delay valve DV1 which, after a period of about 0À5 sees., produces an output which is fed at 80B to the bi-stable element 80 whose output is switched to its port 80 F1. Air supply along the line P8 is thus cut and the valve B1 returns to its closed condition thus causing the action of the oscillator 82, ram 6 and drum 3 to cease. The distributer 18 comprises a slide block (44) which is connected by a plate (45) to one end of a plunger (43) which is movable in a cylinder (42) axially thereof, Fig. 6 (not shown). The block (44) has a cut-out portion (44a) which accommodates a fastener delivered thereto from the shoot 16a, 16b, and movement of the plunger (43) against the action of a spring (42a) causes corresponding movement of the slide block (44) to a position in which the cut-out portion (44a) is located adjacent a fastener guide passage (39) through which the fastener passes to the pipe 50 and is fed to the fastening device 51. The latter comprises an air inlet 60 and outlet 61, Fig. 11, and when it is required to feed a fastener from the distributer 18 to the device 51 the inlet 60 is cut-off from the outlet 61 thereby causing a build-up of pressure which, when communication between the ports 60, 61 is re-established, causes a trigger signal to be sent along a line P5 to a monostable element 79 whose output actuates a bi-stable element 81 which produces an output pulse at 81 F1 which is fed along a line P7 to open a switch valve B2 which permits passage of air to the distributer 18 through a line P2 from the compressor AC. After a predetermined time a timer TM which receives air from the bi-stable element 81 supplies a switching impulse along a line T2 to close the element 81, whereupon operation of the distributer 18 ceases.